Cascaded Trajectory Tracking Control for Automated Vehicles

Abstract

This work deals with the design of a trajectory tracking controller (TTC) for highly automated vehicles. The proposed design follows a modular architecture, composed of an inner velocity loop and an outer trajectory tracking loop. The outer loop, which represents the main focus on this work, is further divided into two parts. The first uses input-output linearization methods to tackle model nonlinearities. The second part exploits Lyapunov methods and convex optimization to enforce physical constraints -e.g. friction circle -and minimize TTC's loss of performance. Simulation results demonstrate that, in comparison with unconstrained TTC methods, the proposed approach is able to reduce tracking errors in up to 50% when the vehicle operates at the limit of friction.